“Until this study, research had not shown whether or not liars could suppress elements of their facial expression as a countermeasure.”

Mark Frank, Professor

Department of Communication

"Executing Facial Control During Deception Situations," a study
he co-authored with former graduate student Carolyn M. Hurley, PhD,
reports that although liars can reduce facial actions when under
scrutiny, they can't suppress them all.

Frank, PhD, a professor of communication at UB, supervised and
co-wrote the study with lead author Hurley, now a research
scientist at the U.S. Transportation Security Administration.

Published earlier this year in the Journal of Nonverbal
Behavior, the study examined
whether subjects could suppress facial actions like eyebrow
movements or smiles on command while under scrutiny by a lie
catcher.

It turns out subjects could to a degree, but not completely and
not always.

The results are derived from frame-by-frame coding of facial
movements filmed during an interrogation in which participants,
some lying, some telling the truth, were asked to suppress specific
parts of facial expressions. Hurley and Frank found that these
actions can be reduced, but not eliminated, and that instructions
to the subjects to suppress one element of expression resulted in
reduction of all facial movement, regardless of their implications
for veracity.

Despite these findings, the majority of the 60 study
participants reported believing that they had controlled all facial
movement and had remained "poker faced" during the
interview/interrogation.

"Behavioral countermeasures," says Frank, "are the strategies
engaged by liars to deliberately control face or body behavior to
fool lie catchers. Until this study, research had not shown whether
or not liars could suppress elements of their facial expression as
a countermeasure.

"As a security strategy," he says, "there is great significance
in observing and interpreting nonverbal behavior during an
investigative interview, especially when the interviewee is trying
to suppress certain expressions."

Click here for
a news interview in which Frank describes elements of his
research.